一个热的巨行星大气中的五种含有碳和的物种
Paolo Giacobbe1, Matteo Brogi2,3,4, Siddharth Gandhi3,4
1INAF-Osservatorio Astrofisico di Torino, Turin, Italy. paolo.giacobbe@inaf.it.
Nature
|April 8, 2021
概括
研究人员在热木星系外行星HD 209458b的大气中检测到多种分子,包括水,一氧化碳和甲. 这表明有丰富的碳组成, 挑战外行星大气层的假设.
科学领域:
- 外行星科学
- 大气化学
- 天体物理学
背景情况:
- 热木星是靠近恒星的气体巨星,
- 之前对热木星的研究发现了水蒸气和一氧化碳,
- 已经对HD 209458b的大气进行了广泛的研究,之前关于检测氨的报道存在矛盾.
研究的目的:
- 在极端辐射下探测热木星HD 209458b的大气组成.
- 研究外行星大气层的化学和物理特性.
- 测试有关热木星大气层组成的假设.
主要方法:
- 使用先进仪器分析系外行星过境的观测天文学.
- 通过系外行星大气层的光谱分析.
- 在辐射和化学平衡下进行大气模型.
主要成果:
- 在HD 209458b大气中检测到水 (H2O),一氧化碳 (CO),化 (HCN),甲 (CH4),氨 (NH3) 和乙烯 (C2H2),具有很高的统计意义.
- 大气模型显示碳含量很高,碳与氧的比率接近或超过1,明显高于太阳值.
- 这些发现挑战了热木星中类似太阳的,富含氧气的组成的普遍假设.
结论:
- HD 209458b 富含碳的大气层表明它可能已经远离它的恒星并向内迁移.
- 检测到的分子丰富意味着其他热木星也可能具有非太阳成分.
- 这项研究需要对热木星大气组成的假设进行重新评估.
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